Apparatus for burning liquid fuel



Nov. 22, 1932. H. F. CLAYTON APPARATUS FOR BURNING LIQUID FUEL Original Filed Jan. 15, 1950 2 Sheets-Sheet Myer/for Nov. 22, 1932.

H. F. CLAYTON APPARATUS FOR BURNING LIQUID FUEL Original Filed Jan. 15, 1930 2 Sheets-Sheet 2 M er/far Harry E G/ay/an Patented Nov. 22, 1932 PATENT OFFICE HARRY F. CLAYTON, F STRATHMORE, QUEBEC, CANADA APPARATUS FOR BURNING LIQUID FUEL Application filed January 15, 1930, Serial No. 420,949. Renewed April 12, 1932.

This invention relates in general to improvements in apparatus for burning liquid fuel, especially oil, and specifically to means for atomizing and to some extent vaporizing the fuel.

An object of this invention is to provide means for generation of steam at substantially constant rate for fuel atomization, independent of the heat realized from burning of the fuel, associated with means to regulate the supply of fuel oil, in such manner that the fuel oil is preheated to a safe temperature below open cup flash point, by heat radiated from the steam generating means, whereby the fuel oil is properly conditioned for subsequent very line and substantially complete atomization.

A further object of this invention is to provide a steam generating and a fuel oil atomo izing unit, wherein preheating of the fuel oil to enhance atomization thereof is effected by heat radiated from the steam generating means whereby it is not possible to excessive- 1y preheat the fuel oil prior to atomization 5 by steam.

In particular. the invention is characterized by its simplicity of construction, wherein the number of parts are few, the design, manufacture and assembly of the components simple, and the cost of production moderate.

According to this invention, apparatus is provided to accomplish the foregoing and other objects comprising, generally speaking, an electrically heated steam generator in cluding a water supply regulator, and a fuel heater and supply regulator associated with one another, preferably in a single casing.

In the accompanying drawings which illustrate a preferred embodiment of the invention but to the details of which the invention is not confined, as modifications may be made in the form and arrangement of the parts Fig. 1 is a vertical longitudinal sectional view of the apparatus.

Fig. 2 is a plan View of same.

Fig. 3 is a horizontal sectional view on the line 33 of Figure 1.

Fig. at is a vertical transverse sectional view on the line i -t of Figure 1.

Referring more particularly to the drawings, 11, 12 and 13 designate a steam generating chamber, a water supply controlling chamber and a fuel supply controlling chamber respectively. As illustrated, these three chambers are axially vertical cylinders formed en bloc with separate bottom heads 14 15 and 16 respectively and separate top heads 17, 18 and 19, respectively, and are enclosed in a thermally insulated casing 20. Obviously, the construction may be altered as to the integral formation of the chambers, the separate formation of heads and the formation of the casing separately from the chambers or their heads. For simplicity of manufacture, all the heads excepting the bottom head 1 1 of the generating chamber 11 are initially formed similarly to one another and each provided with a central boss 21. For the same reason, the chambers may be all of the same dimensions. The bottom head 14 of the generating chamber is preferably of inverted hollow conical form and constitutes a sump below the chamber proper in which sediment and scale may collect. As illustrated, the casing 20 comprises flanged bottom and top plates 22 and 23 respectively, and a vertical wall 24 connected between the flanges of the plates. A layer of heat insulating material, designated 25, is secured to the inner surface of the casing.

The generating chamber 11 is preferably provided with a loose lining or bushing 26 S5 of material not subject to corrosion or electrolysis, such as a suitable type of stainless steel. This lining is in secure electrical and mechanical connection with the head 17 of the chamber and forms what is, for convenience, termed. the ground electrode of the generator. The live electrode of the generator, designated 27, is a hollow cylindrical structure disposed concentrically of the lining and suitably spaced therefrom and from the bottom head and is composed preferably of the same material as the lining. The live electrode is supported by any suitable number of arms 28 offset toward the axis of the chamber and connected to an axially disposed and vertically adjustable stem 29, which passes out of the chamber through any suitable form of electric insulating bushing 30 mounted in the boss 21 of the top head 17. Steam tight joints are formed at the insulator and the stem 29 serves the dual purpose of adjustably supporting the live electrode concentrically within the lower part of the lining and of an electric current conductor. Insulating spacers (not shown) may be inserted between the live and ground electrodes to preserve the concentric relation but, ordinarily, such spacers are not needed since the weight of the electrode is trifling in comparison with its support and the el-ec trio potential difference between the electrodes in service not sufficient to cause distortion. An insulated flexible electric conductor 31 leads from the stem 29, to which it is suitably secured, out of the casing at any suitable point.

Water and steam passages 32 and 33, respectively, connect the generating chamber 11 and water regulating chamber 12 near the bottom and top respectively to secure equal water levels in the two chambers. The water passage 32 is preferably about on a level with or below the bottom of the live electrode. A steam outlet passage 34 leads from the upper part of the generating chamber and extends outwardly of the casing. A valved drain pipe 35 leads from the bottom of the lower head 14 and extends outwardly of the casing.

The bosses 21 of the bottom heads 15 and 16 of the water and fuel chambers are formed with shouldered passages 36 and 37 respectively, into the lower larger enus of which water and fuel pipes 38 and 39, respectively, are screwed. The shoulders of the passages form downwardly facing conical seats 40 and 41 for ball valves 42 and 43 supported by stems 44 and 45 passing loosely through the upper smaller ends of the passages and adjustably connected (as by screw threads) to floats 46 and 47 located in the water and fuel chambers respectively.

' In the'lower part of the fuel chamber 13 an inward projection 48 (best shown in Figure 4) is provided having an axially vertical bore 49 open at top and bottom and shouldered at 50 to provide an upwardly facing seat for a needle valve 51 screwed. into the upper part of the bore. The stem 52 of the needle valve eXtends upwardly through the upper head of the oil chamber and through the top of the casing and is provided with an operating knob 53. A passage 54 leads from the bore 49 immediately above the valve seat and connects with a pipe 55 whichleads out of the casing, preferably at a point near the exit of the steam passage 34. A breather hole 56 is provided in the upper head 19 ofrthe fuel chamberand may be connected with the atmosphere outside the casing by a suitably screened pipe 57. The valve is designed to be entirely submerged in the fuel and therefore does not require packing to prevent leakage. A fuel atomizer 58 is connected to the steam and oil pipes and positioned to direct atomized fuel into a furnace 59.

The operation of the apparatus is as follows Fuel is supplied, preferably by gravity through the pipe 39 to the fuel chamber 13. When fuel accumulates to a predetermined level in the chamber, it lifts the float 47 suf- 'ciently to close the valve 43. The pressure of the fuel supply is against the valve and tends to keep it closed, so that tendency to fuel leaking into the chamber is reduced to a minimum. Water is supplied in asir'nilar manner to the water chamber, preferably by gravity from constant level supply at suit able elevation above the water chamber, and when a predetermined level is attained in the water and generating chambers the float 4G closes the valve 42 against further ingress of water until the level is lowered in the chambers. Assuming the apparatus to be electrically grounded, current is supplied to the live electrode 27 and a discharge takes place between the live and grounded elec trodes through the intervening water which forms a resistance and is thereby heated and converted to steam. The steam is conducted to the atomizer 58 where it serves as motive fluid to lift fuel through the pipe 55 from the fuel chamber. As the water isevaporated. its level in the generating chamber tends to fall and, because of the equalizing passages 32 and 33, the water level in the chamber 12 tends to fall to equal extent. When the apparatus is in operation the water level in the two chambers is substantially constant and supports the float 46 at such level that there is a constant rate of water flow through the valve 42 equal to the rate of evaporation plus any bleeding through the pipe '35 for removal of impurities. The steam pressure in the chambers 11 and 12 is opposed to and preferably equal to the pressure of the water supply, which should be adjusted according to the steam pressure desired. Thus, drop in steam pressure permits greater ingress of water and increase of steam pressure relieves itself by expelling water from the chambers 11 and 12 through the supply pipe and aga nst the supply pressure. The greater influx of water due to falling steam pressure raises the water level and thereby submergcs the live electrode more deeply, with the result that there is greater current input and greater steam production. Obviously, the water cannot rise above the level which causes closing ofthe water supply valve. Lowering of the water level reduces the submergence of the live electrode and thereby reduces the steam production. In theory, a static condition prevails and practice follows the theory very closely- Since relief of exfee cess steam pressure depends on expulsion of water from the apparatus, it is essential that the water supply valve open outwardly (unless a special outwardly opening relief valve is provided). The fuel supply valve is theoretically always slightly open, similarly to the water supply valve, and admits fuel at the rate it is withdrawn from the chamber, so that the fuel level remains constant in the chamber 13.

Production of steam at constant rate and pressure ensures constant suction and atomizing effort at the atomizer and this, coupled with the constant level of the fuel in the chamber 18, ensures a constant rate of atomization. Formation of the fuel chamber en bloc with the generating chamber and enclosed in the same casing therewith enables heat lost from the generating and water chambers by conduction through the chamber walls and by radiation therefrom to be partly utilized to preheat the fuel and, especially when the fuel is a heavy oil, render the same freely fluid, thus reducing its resistance to flow to the atomizer and ensuring a line atomization. The apparatus is self-regulating and, as long at it is supplied with water and fuel, it will enable fuel to be atomized at constant rate. Manual regulation may be effected by means of the valve in the fuel pipe or by regulating the current flow through the generator. Adjustments may be effected by lowering or raising the live electrode or by lowering or raising the floats relatively to their valves or by altering the pressure atwhich water is supplied or by any combination of these three.

The preheating of the liquid fuel in the chamber 13 ensures not only the fluidity necessary for perfect atomization but also induces vaporization of the fuel when released from the atomizer and assists the steam in raising the temperature of the atomized or vaporized fuel near its ignition temperature, so that the fuel will burn with a transparent smokeless flame.

In order to offset the low steam pressure when starting and to facilitate starting, an auxiliary fuel regulating means may be provided. One form of such means comprises a passage 60 paralleling the passage 54L and opening directly into the fuel chamber 13. A vertical passage 61 intersects the passages 5a and 60 near the suction pipe 55 and is controlled by a normally closed needle valve 62. This valve may be operated in any suitable way, for example, by using the valve as the plunger of a solenoid 63 mounted on the wall of the chamber 13 and arranged to open the valve against the pressure of a spring 64. Alternatively, the solenoid may have a second winding to hold the valve closed.

lVhen starting the burner in operation, the valve 62 is opened and the passages and 61 form a second fuel channel between the chamber 13 and the suction pipe 55 to admit a flow of fuel additional to that which passes the valve 51. In this way, a temporary additional fuel supply may be obtained without changing the setting of the valve 51. When the burner is in full operation, the valve 62 is closed. While the valve 62 is preferably electrically actuated as this permits of automatic operation under thermostat control, it will be obvious that the valve may be arranged for manual operation.

Having thus described my invention, what I claim is 1. In liquid fuel burning apparatus, a steam generator including water supply controlling means and fuel supply controlling means closely related and enclosed in a single insulated casing, whereby heat lost from the generator will be partly absorbed by the fuel supply controlling means and fuel therein for preheating of the fuel.

2. In liquid fuel burning apparatus, a steam generator including water supply controlling means and fuel supply controlling means formed en bloc and enclosed in a single insulated casing, whereby heat lost from the generator will be partly absorbed by the fuel supply controlling means and fuel therein for preheating of the fuel.

3. In liquid fuel burning apparatus, a steam generating chamber, a water supply controlling chamber and a fuel supply controlling chamber formed in contact with one another for conduction of heat from one to the other and an insulated casing enclosing fhe three chambers for retention of radiated ieat.

i. In liquid fuel burning apparatus, individual axially parallel cylindrical steam generating, water regulating and fuel regulating chambers in close relation, separate substantially similar bottom and top heads for said chambers and a casing enclosing the chambers including flanged top and bottom plates, a vertical wall connected between the plate flanges and a lining of heat insulating material.

5. A structure according to claim 4, in which the bottom head of the steam generating chamber is of inverted conical form having a valved outlet at its lowest point.

6. In liquid fuel burning apparatus, individual steam generating, water regulating and fuel regulating chambers, including bottom and top heads, a valved drainage outlet at the bottom of and a steam outlet at the upper part of the steam generating chamber, water and steam passages connecting said steam generating chamber with the water regulating chamber near the bottom and top respectively, shouldered passages formed through the bottom heads of the water regulating and fuel regulating chambers, the oulders of said passages constituting downwardly facing valve seats, valves on said seats including stems extending upwardly into the chambers above, floats in the chambers .adjustably connected to the valve stems, a valved outlet from the fuel regulating chamber,

' heating means in the steam generating chamber, an atomizer, and separate connections between the atomizer and said steam outlet and fuel outlet. c

7. In liquid fuel burning apparatus, a

' steam generating chamber and fuel oil supply regulating means, both enclosed in a single insulated casing and so formed and corelated that part of the heat radiating from said steam generating chamber eflects preheating of fuel oil in said fuel oil supply regulating means.

In Witness whereof, I have hereunto set my hand.

HARRY F. CLAYTON! 

